For education and discussion only. Not for commercial use. WASHINGTON - The chirp of the chickadee is charming to humans. To other chickadees, it can convey a lot of vital information. When the little black-capped songbird whistles "chick-a-dee-dee" it can warn flock mates to watch out: A predator is near. Christopher N. Templeton and colleagues recorded the chickadee songs, analyzed them by situation, studied the calls on acoustic instruments, and watched the birds react when the songs were played back. The researchers' findings are reported in Friday's issue of the journal Science. "These birds are passing on way more information...